Fix format size issue

fix #147

src/filters.ts

@@ -3,9 +3,15 @@ import Vue from 'vue';
 
 /* eslint-disable no-param-reassign */
 export function toPrecision(value: number, precision: number) {
-  if (value >= (10 ** precision)) {
+  const limit = 10 ** precision;
+  if (value >= limit) {
     return value.toString();
-  } if (value >= 1) {
+  }
+  if (value >= 1) {
+    if (value >= limit - 1) {
+      return limit.toString();
+    }
+
     return value.toPrecision(precision);
   }
 
@@ -14,18 +20,20 @@ export function toPrecision(value: number, precision: number) {
 
 export function formatSize(value: number): string {
   const units = 'KMGTP';
-  let index = -1;
+  let index = value ? Math.floor(Math.log2(value) / 10) : 0;
 
-  while (value >= 1000) {
+  value = value / (1024 ** index);
+  if (value >= 999) {
     value /= 1024;
     index++;
   }
 
-  const unit = index < 0 ? 'B' : `${units[index]}iB`;
+  const unit = index === 0 ? 'B' : `${units[index - 1]}iB`;
 
-  if (index < 0) {
+  if (index === 0) {
     return `${value} ${unit}`;
   }
+
   return `${toPrecision(value, 3)} ${unit}`;
 }
 

tests/unit/filters.spec.ts

@@ -7,6 +7,8 @@ describe('to precision', () => {
   test.each([
     [0.1, 1, '0'],
     [0.1, 2, '0.1'],
+    [0.9, 1, '1'],
+    [99.5, 2, '100'],
     [122, 1, '122'],
   ])('case %#', (value, precision, result) => {
     expect(toPrecision(value, precision)).toEqual(result);
@@ -18,6 +20,8 @@ describe('format size', () => {
     [0, '0 B'],
     [10, '10 B'],
     [500, '500 B'],
+    [998, '998 B'],
+    [999, '0.98 KiB'],
     [1000, '0.98 KiB'],
   ])('case %#', (value, result) => {
     expect(formatSize(value)).toEqual(result);